N-Wirkung von Rindergülle bzw. Jauche mit Dicyandiamid in Feldversuchen

Utilization of N in cattle slurry and liquid manure with Dicyandiamide in field trials In several field trials on deep loess soils, effects of DCD on utilization of N in cattle slurry and liquid manure by silage maize, sugar beets and turf was tested. DCD inhibited nitrification of NH₄ nitrogen added with slurry or liquid manure and thus decreased losses by infiltration or leaching considerably. If measured as so called “N_min nitrogen” at the start of vegetation, amounts of nitrogen actually present in the soil are underrated in plots with slurry or liquid manure + DCD. Addition of DCD at a rate of 30 kg/ha to slurry and 15–30 kg to liquid manure improved in all cases utilization of N in slurry applied in April or between August and November and of liquid manure applied in November. By use of the nitrification inhibitor Dicyandiamide as complement to slurry or liquid manure it is therefore possible to inhibit decomposition of ammonium nitrogen in these organic manures for 2–4 months depending on temperature, and to “preserve” it during periods without vegetation when soils are especially exposed to leaching. By this means, utilization of slurry-nitrogen by the following crop can be improved considerably.